Accubar SDI-12 Barometric Pressure Sensor Operations & Maintenance Manual Rev-B 30 Nov 2017
pg. 7
4
Setup & Operation
4.1 Introduction
This section will familiarize you with the steps and commands needed to alter the setup of the
ACCUBAR
®
. If you will use the ACCUBAR
®
sensor at address 0 (the factory default) and can accept the
output in units of mB (hPa), you will not need to use these commands. Typically, you will need to issue
some of the commands, so we recommend you learn how to do so. Learning to issue commands also
helps if you need to troubleshoot a sensor.
To issue commands to the ACCUBAR
®
via SDI-12, you will need to connect it to a data recorder, such as a
Sutron 7310, 8210, 8310, 9210, or Xpert which is capable of issuing standard and extended SDI-12
commands. Follow the instructions in Sections 2 and 3 in order to make these connections.
4.2 Nomenclature
All commands have three components: the
device address
, the
command body
, and the
command
termination
.
The
device address
is a single character and is the first character of a command. In the examples that
follow, it is usually the number 0 (the default address as shipped from the factory).
The
command body
and the responses are shown as a combination of upper and lower case letters.
The upper case letters are the fixed portions of the command and the lower case letters are the
variables or values. In the specific examples, you will see that the lower case letters are replaced with
actual numbers.
All commands are shown with an exclamation point (!) as the
command terminator
.
4.3 Setting the Address
If you are using the ACCUBAR
®
connected with other SDI-12 devices, you will need to change the
ACCUBAR
®
address. Otherwise, skip this section. The address simply lets multiple devices share the
same wiring. When the data recorder needs data from a particular sensor, it requests data using an
address. Only the device with the matching address will reply. For convenience in setting up the unit
when only one sensor is connected, the ACCUBAR
®
supports wildcard addresses of asterisk (*) and
question mark (?).
The default address is 0.
Using a Command to Set the Address
Also, no other SDI-12 devices connected to the system should be set to address 0 or to the desired
ACCUBAR
®
address. Hint: if you do not know the address of a particular ACCUBAR
®
, use the unknown
address command to have the ACCUBAR
®
identify itself.
NOTE: There can only be one ACCUBAR
®
connected in order for the unknown address command to
work. The syntax for the unknown address command is
*X?!
